Add the following to your source file /etc/apt/source.list
deb http://old-releases.ubuntu.com/ubuntu gutsy main restricted universe multiverse
deb-src http://old-releases.ubuntu.com/ubuntu gutsy main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu gutsy-updates main restricted universe multiverse
deb-src http://old-releases.ubuntu.com/ubuntu gutsy-updates main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse
deb-src http://old-releases.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse